At last, a sensible policy from Canberra. Employers will first want to employ Australians as it will be cheaper. If an Australian can't be found then the position can still be filled but it would make sense to invest in training as it would be cheaper in the long term.
Some countries have a list of occupations reserved exclusively for locals and these are often at the lower end, such as cleaning or driving, to ensure that there are jobs available for the less skilled and pay rates are maintained at a living wage.